Grinding wheel and method of grinding



Sept. 2()v 1927.

G. WIRRER GRINDING WHEEL AND METHOD OF GRINDING I Filed June 13, 1922 7 UWE/w03 470%@ BY QWS( fw V:fno/mns d P telltod Sept. 20, 1927.

UNITED STATES ao'r'rlmmn Winans., os- YLMNFIELD,

Moron courant', on NEW YORK, vn. GRINDING WHEEL AND Application tiled June 13,

This invention relates to anl improved Wheel for grinding interrupted surfaces oi cylindrical parts and to a method of grind'- ing which is based essentially on a new principle. The general object of the invention is to l'ovide a Yrinding wheel and method ot in ing in w lich the wheel shall always maintained in correct relation to the work and allow a great number oi' redressin rs or truings without. altering the .shape o the grinding face. Heretofore, it is the practice to provide a grinding wheel which is of .such form as to involve, its movei'nent in ailir'ection parallel to the axis of .the grinding wheel. 'lhe method of grinding thus employed requires the use of relatively thin wheels, especially' in rases where the interruptions are narrow and is one, consequently, which ai'ords a very short life of the. wheel. The amount ot stock in known wheels available for trimming without. altering the form of the wheel is so limited as to require constant replacement pt' the entire grinding element.

The principal object ot' the present invention is to provide a grinding wheel which shall always atl'ord, during its lil'e, a relatively great'. bulk of stoel( for dressing or truin'g without altering the form of the wheel or changing the relation of the grinding face to the' work. Another object ls to provide an improved method oi' grinding in which the wheel shall be so mounted to move in such relation to the work as to result in uniform wear on the grinding face while preserving always the proxer relation between such grinding face an the work. More particularly, the improved wheel is one in which the grinding portion is formed as a truncatedcone whose grinding edge is v substantially atright angle'sto the pressure line of the element being ground. 'lhe improved method, in theparticular application thereof to be hereinafter described, contem plates the feeding in of the grindingface to the work along a line parallel to thecone face tothe end that no matter how much the wheel has been cut' ofi' in trimming or dressing the cutting t'ace will always be presented in proper relationto the work.

In accordance with the preferred embodi-v ment ofthe invention a wheel having the characteristics Iindicated above is mounted on a rotatable spindle which may itself beY moved bodily in a direction parallel to the teeth.

vPATENT orric.

NEW JERSEY, ABBIGNOR T0 INTERNATIONAL Y.. 1 3. CORPORATION 0F DELAWARE.

METHQID *GF GBINDING.

i922. aerial No. 567,993.'

cone fece. In the grinding of interrupted surfaces,V such as gear teeth, which involves the introduction of the-grinding element into a comparatively narrow space, it has been desirable in practice to form the improved grinding lip with its grinding face at right angles to tie spindle and at such an angle as will permit its introduction into such space in the element being ground, such as a gear tooth. ln such a case the inside face of the grinding lip will be formed at the same angle so that the grinding face willv always be oi substantially the same 'form and t'limcnsions during its entire'lite.

lt will be understood as the description proceeds that the invention is not to be limited to all of the matters ot' shape and vsize to be yret'erred to hereinafter nor to the use to whirh the improved wheel is to be put but there lhas been selected for the purposes otl this application embodiments of the improvements which are suitable l'or practical work in the grinding ot' geur teeth or rack ln the drawings: .Figure 1 is a view in plan of an improved grinding wheel so mounted as to permit the practice of the improved method when employed for the grinding of gear teeth.

Figure 2 is a view in-cnd elevation of\a portion ol'4 the parts shown in Figure 1.

Figure 3 is a schematic View showing the relation of the cutting face oi an improved wheel to the teeth `of a rack where the spaces are deep and narrow.

Figure 4 shows the wheel illustrated in Figure Il after repeated dressings or trinimmgs. 1

The drawings are intended to be somewhat diagrammatie in character it being unnecessary ior an, understandingc the invention to emphasize an of the details of construction of the maciine on which the improved wheel may be mounted in such a manner as to practice the improved method. Asa-shown in Figure 'l the Wheel a in so far as concerns the grinding element carries, or has formed integral therewith, a generally conical grinding lip a. The outer face a2 oi'; the tgrinding element is .preferably formed parallel to the inner face a and the inclination and thickness of the grinding element a" are such as to permit the grinding face (tAk thereof to be moved into the desired relation with the face of the tooth c and without interference by the adjacent L 'e with respect to the feces a, o3., of the u tooth al? when the grinding element is lied egemst the worlr meng e line pereilel to the cone niece. iii the lip were mede Cireulnr rather than conieel il; is evident that outer fece would engnge the element to loe ground, es et die bottoni ol tootn when the rnding edge Wes moved to the loose of i e tooth. This is objectionable and would limit the usefulness of the Wheel. lin

'so ier es eonceirns the physico-l structure oi lei?. euch es eerhorundum The weer on the grinding element, in cese, is on the grinding feceul nrhieli is only partei the elem it which engages the surfeee 'of the Work. This grinding with ite sharpl edge iney he movedfyto the Tonse of e tooth ysind the singularity oi out-er edge of 'the ilove/ill prevent oon t thereof with thelhottoni or otherpe: the Work to loe ground. 'llhis ieee is formed at right ongles to the finis of the 'wher so that, es i lustreted in Figure l, nl'

o is complementary to the angle The improved method oli grinding has to do with the relation mninteined between the grinding ieee of end the `ieee of the work so as to insure uniform weer on the 'leee sind adapt et ell tiinesfor ready trimming' oi" dressing by means of en element which .may be mountedin such relation thereto es to Jfacilitate the trimming. As indicated hereinbefore, the invention is not to be limited 'to the details of construction of thegeloments employed 'lor mounting the frindiing element ci so to practice t .-ev improved method and foi-.that reason suoli elements are shown indiegremmetic form in the eecompenying drawings,

The Wheel a, es illustrated.7 may he .mounted on a spindle f which carries driving'puh leys ff wherebyy rotative movement is irnperted 'to the spindle and Wheel from any available source of power, end the spindle is journeled in suitable bearings g, g', cerried on'oplete Il, which is, in turn, supported on o slide The slide e" is mounted to travel" in' under-cutiwnys ,Ic formed in the supporting table yZ for the machine. The plate /L may be ,adjusted engularly on the slide z' and set in any desired angular posih tion thereon by means of bolts z" the reason for "this adjustment being pointed out more perticularl Y hereinafter yin connection with the descrifltion of the improved method of operation. Further adjustment may he effooted by swivelinp; the bese le on the table Z so their. it 'may be swung e-ngulerly for the wheel will be `nroyided, generally speaking,y

purpose of bringing the grinding ieee o* or the 'Wheel et righe engl-es to the pressure grinding element extended to intersect the en *"2 Thee-elio s lli, in the preferred rel ere perellel the sone )ieee i rer the purposes of the de Y he considered es the line ppeers lyirom 'Figure l 'the-t 'the eene A! is,- ieernllel to 'i' Wliioh indicates the direction of travel oi the sliden setting' np'lihe `t/vl'ieel for e, grinding operetion the loe-sell: Will he set in such' enf geler reletion es to present the' fece o* properly to the worlr, i. e. preierehly et right ongles 'to the pressure line. Since e diherent for the grinding oit dilieren; Work, depen. ing upon the pressure anglo, the angular poi tion olf the bese fc Will he changed 'for each di ,nt wheel to rneintnin 'the enguler .elet-ions described herein. fllor feeding in he wheel properly for eny viven pressure ongle, the plete Ii will be adjusted engulzirly' on 'the slide i so that the slide will move parallel. ln operation, with the ports set in the relations described 'the fece e of the grind.- ing element o will loe moved into grinding engagement with the fece of the tooth o oy movement oi' the slide i along the line of travel i2 which is parallel to the cone ieee A2. W hen the gein." is rolled on its exis 'to present different portions of the tooth o to the face of* the relation of parte will he maintained sind weer on the grinding element awill take place uniformlyvand. steadily over 'the grinding face a' and from the outer edge a2 to' the inner edge aof the grinding element. rlhe bulli: or unused grinding materiel in the lip/a is meesuredv were originally provided. It is evident, of

course, that the dimensions of the rindin element a and its engulerity Wien fe l against the tooth c along e line of travel indicated et e" must be such es to 'enable its outer edge azto clear the adjecent`tootl1' d While enabling 'the ground tooth c to he en-y raged hy the grinding fece a clear to its bese. ln eeeli o1"- 4these figures the cone fece is indicated et A? end the line of travel or the grinding element at '7, these two lines belngpa'rellel. The angular relations describe with res ect to the Wheel in Figure .l are nieinteinec regerds the exis oi roto is) mond and rocking of the tion, the cone face and the line of travel of the supporting slide, all bein iired-v in conformity to the pressure angle o the work being ground. Figure 4 shows the wheel 5 illustrated in Figure 3 after repeated triinmings of the grinding lip and shows inthe' last View the limitation of its 'usefulness wherein the lip has been completely trimmed away and the grinding material ies in the l plane f the disk. In each successive trimming the form of the grinding face is preserved and isa maintained in a planeat right angles to the axis of rotation.

While the present invention is not to be l limited to the character of the trimming inechaiiism employed there has been shown one convenient forni which permits the trimming to be carried on without changing the relation of the angles initially set up for l practice of the grinding method in accordance with the description hereinbefore given. The table Z may have mounted pivotally thereon as on a racket Z a swinging bell-crank m in one arm of which is maintained a diamond m and on the'other arm beformed a convenient hand-y of which ma grip to faci itate rocking of the bell-crank on its pivotal supportgThe supporting bracket Z may be rotatably adjusted and zo, secured in any desired angular position by `suitable adjusting devices illustrated as a locking'bolt Z2. By revolving the bracket Z about its pivotal support the bell-crank m may be brought into parallelism with the grinding face a* of the grinding element a.

may be carried on as desired Without disturbing the relationship between the elements employed in theinountiifigof the grinding parts and enables the diamond m',

to be moved out of interfering relation with 5o the grinding elements a when desired. This movement, indeed, may be vfacilitated by mountin the table Z on a slide as indicated at Z so t iat all of the parts thereon ma be moved towards and awa from the bracket Z as by.. inanipu ation of a handwheel Z4, in a marinai` commonly practised.

As indicated hereinbefore. the invention isf not to be limited to details of construction of any of the. parts illustrated or described nor to the character of the trimming 'mech-4 l"anisin, since in its broader aspects the inven- "work along,r a line parallel to the cone face.

2'. A rgrinding element o generally conical form in which the cone angle is such as to permit the element to clear the ,work t0 be ground, a spindle on which the grinding element is rotatably mounted, arid a slide on whichthe spindle is mounted movable at an angle to the axis of the spindle equal to the angle between the cone face and itsaxis.

3. In combination, a grinding element of generally conical form havin a grinding face on its end, a spindle on which the grinding elementis rotatably mounted, a slide 0n which the spindle is supported, means to adjust the slide angularly to bring the grinding face in predetermined relation to the work to be ground, and means to adjust the angle of the spindle with res ect to the slide whereby the line of feed o the grinding element into the work may be adjusted.

4. The herein described method of g. inding which consists in applying a grinding wheel to the work to be ground, moving the faces thereof relatively and feeding in the wheel along a line parallel to the cone face. vThis specification signed `this 23rdday of May, A. D. 1922. c v

GOTTFRIED WIRRER. 

